Dump Control / LVD Circuit

[TomW]

The turbine is ALWAYS connected directly to the battery.

The dump load uses Battery power.

The turbine connected to the battery will be at the battery voltage.
If it is connected to the battery, it can not be anything except the battery voltage.
This fact is known as "KVL".

Because the turbine is ALWAYS connected directly to the battery, there is no 40V to be concerned with.

G-

Be nice if people could get that battery being controlled part right. It is a point of confusion for so many.

It is just so simple once you get it in your head that you control the BATTERY and the turbine is clamped to battery voltage (plus the rectifier drop of course). While you control the battery volts the turbine just conveniently follows along fully loaded by the battery.  Sure makes life simple.

OFF TOPIC FOLLOWS:

BTW, Glen, Still running the GHurd Controller driving the IGBT brick abuse test into fourth week now. Outback really screwed the pooch on this process. Convoluted tech support process to determine what I already told them, lost shipping order, late next day air on the fix for that then dead inverter again  after 5 minutes of operation. when I finally got them. Boards were supposed to be "new" but I obviously got either refurbished or something certainly not new. Sorry to divert but after 3+ weeks with a dead unit I may post a vent diary later today. Very disappointed in Outback.

Tom

[naveenck]

Hello G,

Thanks a lot for clarifying about the wind turbine -> Battery connection. From what I have read, wind turbine produces AC like voltage which needs to be rectified to DC which can charge battery. I need to ask you a basic question here, please bear with me.

Does the Wind Turbine you are considering here, have rectifier and voltage limiting circuit built in ? If so, please give me some links to such wind turbine. If not, can the AC voltage charge Lead Acid Battery directly ?

Also, if I consider charging batteries by Pedaling a Bike, will the Dump Load controller need to be modified or will it work as is ?

Thanks in advance,
Naveen

[ghurd]

A dump load or diversion controller controls the Battery.

The controller does not care if the power comes from wind, solar, hydro or anything else.
Pedaling is covered with 'anything else'.
All wind turbines are covered under 'wind'.

The turbine connected to the battery will be at the battery voltage.
The battery limits the turbine voltage.

Batteries can not be directly charged with AC.
If they could be directly charged with AC, then we would not waste money and effort on rectifiers.

[ghurd]

Sorry, but it is time for a price increase.  16% is not that much.

New price for the kit is $14.50

Shipping is still $3 flat rate per order to anywhere.
Example:  1 kit, or 3 kits and extra small parts, shipped to anywhere on the planet, is US$3 shipping.

G-

[TomW]

Sorry, but it is time for a price increase.  16% is not that much.

New price for the kit is $14.50

Shipping is still $3 flat rate per order to anywhere.
Example:  1 kit, or 3 kits and extra small parts, shipped to anywhere on the planet, is US$3 shipping.

G-

Yeah, just proof you joined the ranks of evil rich guys exploiting the masses! 

Tom

[ghurd]

Bump.

Just to see if it fixes the missing photos.
G-

[dave ames]

YEAH !

Great to see the images restored to some of these broken threads.


Dave



Edit: removed a link to "the wayback" machine.

Edit 2: Well gee, I should mention how easy these are to solder up and tune in.

[zvizdic]

Hello G

I think you should post a 48V controller and start selling 48V modifications kits.

I started to use from december 2010 and it is ben running flawless .

So it is fear to say tested and proved to work.

Thanks for a cheap and durable product !

[DamonHD]

Indeed,

${UNSOLICITED_TESTIMONIAL} from me too.  I have so little wind power that it's not a critical component for me, but it does work like a treat!

Rgds

Damon

[georgec]

here I go reviving an old thread.
been lurking for years looking up stuff, this spring I was considering getting a couple panels and rig up a 24v system to run some power tools maybe the idea is to take 24v cordless tools and either make extension cords for them to run directly off the 24 v battery bank or maybe charge the individual tool packs, heck maybe I can use the original tool packs as dump loads? remains to be seen.

Anyway I see the circuit can be used as a dump controller OR lvd, not both if I am not mistaking, so if this was the route I was taking I should get 2 kits? to use one as a charge controller and one as an LVD?

I recon if I will be running power tools I could at times over discharge the bank as well as over charge it if not used.

so that being said I am a bit out of touch, I know some stuff as in 1 panel aprox 18 v good for charging 1 battery 12v, 2 panel in series 2 batteries in series, my understanding is those get connected directly while the circuit monitors the battery voltage.

question is what are the proper numbers for overcharge and over discharge for lead acid?, I see the board can be customizable to each liking just asking of what are common practices,

I have some recycled laptop batteries for example lipo is full at 4.2v, 3s makes 12.6 full I see 14.4v is common for lead acid as a dump point so in theory say I were to build a couple of those lipo packs for the tools, they like amps very much, they could be used as dump loads I reckoned,  and charge off the excess, granted one would than have to be careful and make sure one of those tool empty packs is always connected as a dump load or something else is in its place.

anyway some input would be much appreciated, I am supposed to be shopping here shortly, granted I can get a commercial unit thou I don't know much about them nor weather they can also monitor lvd, I'm sure they are pricy and besides I like dealing with the little guy, and build stuff myself, this is simple enough I can understand

[SparWeb]

Your first question:  yes, the LVD is a separate function and you need a separate board if you also want a charge controller.

Batteries-
Most Lead Acid batteries have such similar chemistry that the voltage set-points can be the same.  Especially for flooded lead-acid batteries (the vast majority of consumer types of LA batteries).  However they work by venting gas when they are changed.  If they can't do this, then pressure builds inside them when they charge.  When dealing with sealed batteries, the battery is designed to withstand a certain charge rate without too much pressure inside.  You then regulate that charge by limiting the voltage to a lower level, one that is safe for the battery case.

So to be specific, flooded lead-acids can and should be charged up to 15 volts and many can take 16v if necessary. 
The sealed lead-acid batteries vary.  I have a set whose absolute maximum is 14.1V, but some can be less others can be more.
With a bit of research I'm sure you'll get a handle on this.

What could give you trouble is using LiPo and Lead in the same bank, or using other batteries as a "dump load" which probably won't work.
If it's just solar you're going to use, then the charge controller just pulses the panels on/off/on/off rapidly, so that the average current doesn't over charge the batteries.  Simple as that, you don't need a diversion load.  It's not like a wind turbine that always has to be ON or else it runs away.